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Mini-Quiz: Effect of Dark Matter and Dark Energy on Gravitation

by Ron Kurtus

Take this Mini-Quiz to check your understanding of the lesson material.

1. How is the mass of a galaxy approximated from the velocity of its stars?

From the equation E = mv2/2

By the equation for circular gravitational orbits

Velocity affects luminosity and thus the mass

2. What is the reason for proposing dark energy?

It is a way to explain the expansion of the Universe

Something is necessary to counter dark matter

It is a way to explain energy observed at night

3. What is an alternative theory to dark matter?

Dark anti-matter

Changes in Newton's laws for high speeds and large separations

Matter comes in various colors and shades

If you got all three correct, you are on your way to becoming a Champion in Physics. If you had problems, you had better look over the material again.

Celebrate your successes

Resources and references

Ron Kurtus' Credentials


Dark Matter - Wikipedia

Cosmic Hide and Seek: the Search for the Missing Mass - Chris Miller

Dark Matter - Dr. Martin White - Astronomy Dept. Univ. of California-Berkeley

Dark Matter Essay - Joe Silk - Astronomy Dept. Univ. of California-Berkeley

Dark Energy - Wikipedia

Dark Energy - NASA

Gravitation Resources


(Notice: The School for Champions may earn commissions from book purchases)

The 4-Percent Universe: Dark Matter, Dark Energy, and the Race to Discover the Rest of Reality by Richard Panek; Houghton Mifflin Harcourt (2011)

Dark Side of the Universe: Dark Matter, Dark Energy, and the Fate of the Cosmos by Iain Nicolson; The Johns Hopkins University Press (2007)

Einstein's Telescope: The Hunt for Dark Matter and Dark Energy in the Universe by Evalyn Gates; W. W. Norton & Company (2010)

Top-rated books on Gravity

Top-rated books on Gravitation

Questions and comments

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Gravitation topics

Mini-Quiz: Effect of Dark Matter and Dark Energy on Gravitation

Gravity and Gravitation

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Center of Mass

Orbital motion

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